The eye, the window of the soul, is the chief means whereby the understanding can most fully and abundantly appreciate the infinite works of Nature; and the ear is second.

Nature is constrained by the cause of her laws which dwell inborn in her. Variant: Nature is constrained by the order of her own law which lives and works within her.

He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.

Whoever does not respect life, does not deserve it.

If you do not rest on the good foundation of nature, you will labour with little honor and less profit.

Nothing is hidden under the sun.

Make your faces so that they do not all have the same expression, as one sees with most painters, but give them different expression, according to age, complexion, and good or bad character.